Spinal Fusion For Adolescent Idiopathic Scoliosis Research Articles

Complications following surgical treatment of adolescent idiopathic scoliosis: a 10-year prospective follow-up study.

Accurate reporting of long-term complications of surgical treatment of adolescent idiopathic scoliosis (AIS) is critical, but incomplete. This study aimed to report on the rate of complications following surgical treatment of AIS among patients with at least 10years of follow-up. This was a retrospective review of prospectively collected data from a multicenter registry of patients who underwent surgical treatment for AIS with minimum 10-year follow-up. Previously published complications were defined as major if they resulted in reoperation, prolonged hospital stay/readmission, neurological deficits, or were considered life-threatening. Rates and causes of reoperations were also reviewed. Two hundred and eighty-two patients were identified with mean age at surgery of 14.6 ± 2.1years. Mean follow-up was 10.6 (range 9.5-14) years. Eighty-seven patients had anterior spinal fusion (ASF); 195 had posterior spinal fusion (PSF). The overall major complication rate was 9.9% (n = 28) in 27 patients. Among PSF patients, the complication rate was 9.7% (n = 19) in 18 patients. The complications were surgical site infection (37%), adding-on (26%), pulmonary (16%), neurologic (11%), instrumentation (5%), and gastrointestinal (5%). In ASF patients, the complication rate was 10.3% (n = 9) among nine patients. The complications were pulmonary (44%), pseudoarthrosis (22%), neurologic (11%), adding-on (11%), and gastrointestinal (11%). The reoperation rate was 6.0% (n = 17) among 17 patients. Although most of the complications presented within the first 2years (60.7%), surgical site infection and adding-on were also seen late into the 10-year period. This is the largest prospective study with at least a 10-year follow-up of complications following spinal fusion for AIS, the overall major complication rate was 9.9% with a reoperation rate of 6.0%. Complications presented throughout the 10-year period, making long-term follow-up very important for surveillance. Therapeutic II.

Does Navigation Make Spinal Fusion for Adolescent Idiopathic Scoliosis Safer? Insights From a National Database.

Retrospective Cohort. To evaluate the effect of computer-assisted navigation (NAV) on rates of complications and reoperations after spinal fusion (SF) for adolescent idiopathic scoliosis (AIS) using a nationally representative claims database. Significant controversy surrounds the reported benefits of NAV in SF for AIS. Previous studies have demonstrated decreased rates of pedicle screw breaches with NAV compared to free-hand methods but no impact on complication rates. Thus, the clinical utility of NAV remains uncertain. Analyses were performed using the IBM MarketScan databases. Patients aged 10 to 18 undergoing SF for AIS were grouped by use of NAV. Patients with nonidiopathic scoliosis were excluded. Univariate and risk-adjusted multivariate analyses were performed. Primary outcomes were neurological complications, any medical complications, and reoperations. Secondary outcomes included adjusted total reimbursements and length of stay. A total of 12,046 patients undergoing SF for AIS were identified, and 8640 had 90-day follow-up. NAV was used in 467 patients (5.4%), increasing from 2007 to 2015. After risk adjustment, the odds for any complication within 90 days were lower with NAV (OR = 0.61, P = 0.025), but neurological complications were unrelated to NAV (P = 0.742). NAV was not associated with reoperation within 90 days (P = 0.757) or 2 years (P = 0.095). We observed a $25,038 increase in adjusted total reimbursements (P < 0.001) and a 0.32-day decrease in length of stay (P = 0.022) with use of NAV. In this national sample, NAV was associated with a lower rate of total complications but no change in rates of neurological complications or reoperations. In addition, NAV was associated with a large increase in total payments, despite a modest decrease in hospital stay. Considering the increasing popularity of NAV, this study provides important context regarding the utility of NAV for AIS.Level of Evidence: 3.

Proximal Junctional Kyphosis Following Adolescent Idiopathic Scoliosis Correction

Proximal junctional kyphosis (PJK) following surgical correction of adolescent idiopathic scoliosis (AIS) is a postoperative radiographic finding observed in the sagittal plane. Development of PJK has not been shown to lead to a negative clinical outcome following spinal fusion for AIS. Long-term satisfactory outcome following spinal deformity surgery is related to the status of the sagittal plane. Proper understanding and prevention of PJK in AIS surgery is needed to preserve the best sagittal plane following surgical correction of AIS.

Preoperative supine traction radiographs often result in higher Lenke classifications than supine bending radiographs in adolescent idiopathic scoliosis.

Retrospective chart and radiographic review. The purpose of this study is to determine if both traction and side-bending radiographs yield the same Lenke classification. Supine side-bending radiographs are used to evaluate curve flexibility and assign Lenke classification in Adolescent Idiopathic Scoliosis (AIS). Supine traction radiographs are another tool used by treating surgeons to gauge flexibility and appropriate levels for spinal fusion in AIS. Retrospective chart and radiographic review were performed on AIS patients that underwent a posterior spinal fusion from 2008 to 2017. Cobb angles and Lenke classifications were determined on all upright posterioanterior (PA) spine radiographs, supine traction radiographs, and four supine bending radiographs. Statistical analysis using independent t tests and chi-square tests as appropriate were compared between patients with or without discordant Lenke classifications with p value set at < 0.05 for statistical significance. 184 patients met inclusion criteria, 36 males and 148 females. The average Cobb angle for the proximal thoracic (PT) curve was 27.2°, main thoracic (MT) curve was 60.5°, and thoracolumbar/lumbar (TL/L) curve was 48.0°. Significantly less curve correction was found with supine traction radiographs compared with bending radiographs: PT (23.1° vs 18.9°, p < 0.001), MT (38.9° vs 37.9°, p = 0.015), and TL/L (25.9° vs. 18.0°, p < 0.001). Lenke Classification was found concordant in 151/184 (82.1%). Traction views in the discordant Lenke classification group demonstrated less curve correction than those in the concordant group: PT (27.4° vs. 22.1°, p = 0.011), MT (45.3° vs. 37.5°, p < 0.001), and TL/L (29.3° vs 25.1°, p = 0.019). Supine traction and supine bending radiographs provided a concordant Lenke classification 82.1% of the time. However, supine traction radiographs demonstrate less curve correction, a higher Lenke classification, and underestimated the TL/L curve correction to a greater degree. A single supine traction film is not an adequate substitute to side-bending radiographs when determining Lenke classification in patients with Adolescent Idiopathic Scoliosis. III.

What are parents willing to accept? A prospective study of risk tolerance in AIS surgery.

Surgical treatment of Adolescent Idiopathic Scoliosis (AIS) involves healthy individuals with spinal deformity. Parents are responsible for surgical consent on behalf of their children, a burden which causes trepidation and concern. Therefore, explanation of operative risk is a critical component of informed consent and parent decision-making. We set out to quantify parental risk aversion (RA). RA questionnaires were administered preoperatively to parents of 58 AIS patients undergoing spinal fusion (SF). RA is the likelihood of a parent to consent to their child's SF (1- least likely, 10- most) with increasing allotments of data about potential complications at each stage (S1-complication named, S2-explained, S3-incidence given, S4-all information). A statistically significant mean difference in answers for each stage was assessed using paired sample t test or Wilcoxon rank t test. Normality was assessed by performing Shapiro-Wilk test. AIS patients (age 14.2 years, 85% female, major curve 61°) were included. Mean scores for each of the stages were 4.4 ± 3.1, 4.9 ± 3.1, 6.5 ± 3.0, 6.6 ± 3.0, respectively. Highest and lowest RA were reported for death and infection, respectively. The greatest increase in likelihood to proceed with surgery was seen after education on malposition of implants and on death, 2.6 and 2.5, respectively (p < 0.001). The lowest increase in likelihood to proceed with surgery was seen after education on infection, 1.5 (p < 0.001). For all complications, there was an increase in parent willingness to proceed after providing descriptions and occurrence rate with a mean increase from S1 to S4 of 2.1 (95% CI 1.4-2.4), p < 0.001. As more detailed information was made available regarding potential complications with SF for AIS, parental RA toward surgery decreased and their willingness to proceed with surgery for their child improved.

Patient-reported Outcomes Following Surgical Intervention for Adolescent Idiopathic Scoliosis: A Systematic Review and Meta-Analysis.

This was a systematic review and meta-analysis. This study aims to perform a systematic review and quantitative meta-analysis of patient-reported outcome measures after spinal fusion for adolescent idiopathic scoliosis (AIS). Radiographic correction of scoliosis is extensively reported in the literature but there is a need to study the impact of spinal fusion on patient-reported outcome measures. Prior reviews lacked homogeneity in outcome measures, did not perform quantitative meta-analysis of pooled effect size, or interpret the results in light of minimally clinically important difference thresholds. A systematic review of medical databases identified all studies that prospectively reported Scoliosis Research Society (SRS)-22 questionnaire data after spinal fusion for AIS. We screened 2314 studies for eligibility. Studies were included that reported preoperative and postoperative data at 24- or >60-month follow-up. Studies were excluded that failed to report means and SDs which were needed to calculate Cohen d effect sizes and 95% confidence intervals in estimating the magnitude and precision of the effect. A total of 7 studies met eligibility criteria for inclusion in quantitative meta-analysis of effect sizes and 95% confidence intervals. Patients report large improvements in total score, self-image, and satisfaction; and moderate improvements in pain, function and mental health at 2 and 5 years after spinal fusion for AIS. All domains showed statistically significant improvement at all times except function at >60 months. All domains surpassed the minimally clinically important difference at all times except mental health. Moderate evidence suggests that spinal fusion improves quality of life for adolescents with idiopathic scoliosis in medium and long-term follow-up. Our results may help inform patient expectations regarding surgery. Level I-systematic review and meta-analysis of prospective studies.

Posterior spinal surgery for adolescent idiopathic scoliosis does not induce compensatory increases in distal adjacent segment motion: a prospective gait analysis study

Background ContextPatients with adolescent idiopathic scoliosis (AIS) perform surprisingly well after spinal correction and fusion. It was previously hypothesized that, during gait, certain mechanisms compensate for the loss in spinal motion. Still, previous studies could not identify such compensatory mechanisms in the lower body. PurposeThis study aims to test the hypothesis of a compensatory increased motion of the distal unfused part of the spine during gait after posterior spinal correction and fusion. StudyThis is a prospective gait study. Patients and MethodsTwelve patients with AIS were included. Sets of three VICON skin markers were used to measure the 3D motion of the proximal part of the fusion in relation to the pelvis (PFP) and the distal part of the fusion in relation to the pelvis (DFP). By doing so, PFP represents the motion of the fused and unfused parts of the spine, and DFP represents the motion of the unfused part of the spine. Measurements were performed preoperatively and 3 and 12 months after posterior spinal correction and fusion. ResultsSurgery resulted in a decrease in PFP transversal plane range of motion (ROM) (8.3° vs. 5.9°, p=.006). No compensatory increase in the ROM of DFP could be identified. Actually, DFP transversal plane ROM also decreased (8.2° vs. 5.6°, p=.019). No improvement over time was observed when comparing the 3- and 12-month postoperative measurements. ConclusionsThe hypothesis of a compensatory increase in motion of the distal unfused segments after spinal fusion for AIS is a much researched and controversial topic. This study is the first to study this hypothesis in such detail during gait and could not demonstrate such increase.

Intratrunk Coordination During High-Effort Treadmill Running in Individuals With Spinal Fusion for Adolescent Idiopathic Scoliosis.

The purpose of the study was to determine if the intratrunk coordination of axial rotation exhibited by individuals with spinal fusion for adolescent idiopathic scoliosis (SF-AIS) during running varies from healthy individuals and how the coordination differs among adjacent trunk-segment pairs. Axial rotations of trunk segments (upper, middle, lower trunk) and pelvis were collected for 11 SF-AIS participants and 11 matched controls during running. Cross-correlation determined the phase lag between the adjacent segment motions. The coupling angle was generated using the vector coding method and classified into 1 of the 4 major, modified coordination patterns: in-phase, anti-phase, superior, and inferior phase. Two-way, mixed-model ANCOVA was employed to test phase lag, cross-correlation r, and time spent in each major coordination pattern. A significantly lower phase lag for SF-AIS was observed compared with controls. Qualitatively, there was a tendency that SF-AIS participants spent less time in anti-phase for middle-lower trunk and lower trunk-pelvis coordinations compared to controls. Phase lag and anti-phase time was significantly increased from cephalic to caudal segment pairs, regardless of group. In conclusion, SF-AIS participants and controls displayed similar patterns of intra-trunk coordination; however, the spinal fusion hindered decoupling of intra-trunk motions particularly between the lower trunk-pelvic motion.

Spine kinematics exhibited during the stop-jump by physically active individuals with adolescent idiopathic scoliosis and spinal fusion

Background ContextIndividuals with adolescent idiopathic scoliosis post spinal fusion often return to exercise and sport. However, the movements that individuals with spinal fusion for adolescent idiopathic scoliosis (SF-AIS) use to compensate for the loss of spinal flexibility during high-effort tasks are not known. PurposeThe objective of this study was to compare the spinal kinematics of the trunk segments displayed during the stop-jump, a maximal effort task, between SF-AIS and healthy control groups. Study DesignThe study used a case-controlled design. Materials and MethodsTen SF-AIS (physically active, posterior-approach spinal fusion: 11.2±1.9 fused segments, postop time: 2±.6 years) and nine control individuals, pair matched for gender, age (17.4±1.3 years and 20.6±1.5 years, respectively), mass (63.50±12.2 kg and 66. 40±10.9 kg), height (1.69±.09 m and 1.72±.08 m), and level of physical activity, participated in the study. Individuals with spinal fusion for adolescent idiopathic scoliosis and controls (CON) performed five acceptable trials of the stop-jump task. Spatial locations of 21 retroreflective trunk and pelvis markers were recorded via high-speed motion capture methodology. Mean differences and analysis of covariance (jump height=covariate, p<.05) were used to compare the groups' relative angle (RelAng) and segmental angle (SegAng) of the three trunk segments (trunk segments=upper trunk [C7–T8], middle trunk [MT: T9–T12], lower trunk [LT: L1–L5]) for each rotation plane in the three phases of interest (flight, stance, and the vertical flight phases). ResultsNo significant group differences for jump height and RelAng were detected in the three phases of stop-jump. Individuals with spinal fusion for adolescent idiopathic scoliosis displayed 3.2° greater transverse plane RelAng of LT compared with CON (p=.059) in the stance phase. Group differences for RelAng ranged from 0° to 15.3°. For SegAng in the stance phase, LT demonstrated greater SegAng in the sagittal and frontal planes (mean difference: 3.2°–6.2°), whereas SegAng for MT was 5.1° greater in the sagittal plane and had a tendency of 2° greater displacement in the frontal plane (p=.070). In the vertical flight phase, greater LT displacement in the frontal plane was observed for SF-AIS than CON. In the flight phase, LT had a tendency for greater SegAng for SF-AIS than for CON in the transverse plane (p=.089). ConclusionsOverall, SF-AIS who participate in physical activity on a regular basis are able to demonstrate similar trunk kinematics during a high-intensity stop-jump task as their matched healthy peers. Fewer group differences for relative angular displacements of the spine were observed than anticipated. This finding suggests that the fused MT appeared to be moving synchronously with the LT, thereby suggesting a compensatory adaptation of SF-AIS to achieve sufficient trunk movements during this high-effort movement.

Pre-Operative Autologous Blood Donation Does Not Affect Pre-Incision Hematocrit in Adolescent Idiopathic Scoliosis Patients. A Retrospective Cohort of a Prospective Randomized Trial.

Pre-donation of autologous blood prior to spine fusion for adolescent idiopathic scoliosis (AIS) has been used in deformity surgery. The effect of pre-donation on pre-operative hematocrit (Hct) remains debated. Multiple factors may influence pre-operative Hct including intravascular volume status, patient factors, and timing of pre-operative blood donation. The purpose of this study was to determine if pre-donation significantly lowers pre-incision Hct in AIS patients. A retrospective cohort study of a Level-1 prospective randomized trial was conducted. 125 patients from the homogeneous population were included. AIS patients undergoing a posterior only spinal fusion for AIS were separated into two groups based on their pre-operative blood donation history. Demographic variables, pre-incision Hct, and transfusion rates were compared between the two groups using the Student's T-test. Pre-donation and non pre-donation groups had 28 and 97 patients, respectively. Pre-donation group was 75% female (21F, 7M) and non pre-donation group was 78% female (76F, 21M). There was no difference between pre-donation and non pre-donation groups in mean age (15.6 ± 2.2 vs 14.8 ± 2.2, p = 0.081), BMI (23.1 ± 4.2 vs 21.7 ± 5.3, p = 0.219), and pre-incision Hct (32.8 ± 3.4 vs 33.8 ± 3.1, p = 0.628). The overall transfusion rates were equivalent (32.1± 48.0% vs 25.8 ± 44.0%, p = 0.509), however, the rate of allogenic transfusion for the pre-donation group was significantly lower (3.6 ± 18.9% vs 25.8 ± 44.0%, p = 0.011). This study supports the use of pre-donation for AIS, without a significant drop in pre-incision Hct. Patients that donate are also much less likely to be exposed to allogenic blood. There may be a surgeon bias to recommend pre-donation in patients with a larger BMI and older age. Future studies are needed from a larger population of patients including those with non-AIS pathology. Level III.

Unintended Change of Physiological Lumbar Lordosis and Pelvic Tilt After Posterior Spinal Instrumentation and Fusion for Adolescent Idiopathic Scoliosis: How Much Is Too Much?

Study DesignRetrospective review of prospective multicenter adolescent idiopathic scoliosis (AIS) database. ObjectivesTo investigate the effect of decreased lumbar lordosis (LL) on measured pelvic tilt (PT) after posterior spinal instrumentation and fusion for AIS and to test the hypothesis that lumbar spinal fusion resulting in mismatched LL is associated with increased PT. Summary of Background DataInteraction between the spine and pelvis highly influences global sagittal alignment (GSA). In adults, correlation between health-related quality of life measures and LL proportional to a patient-specific pelvic incidence (PI) has been established, although the implications of poor sagittal alignment are less well-defined in AIS. This observation warrants further examination of regional spine contour and its relation to the pelvis in AIS. MethodsThe authors queried a prospective multicenter database for AIS patients who underwent posterior spinal instrumentation and fusion with lowest instrumented vertebra between L2 and L5 and identified 155 patients with minimum 2 years' follow-up. Lumbar lordosis (T12–S1), LL within fusion, LL below fusion, GSA, PT, and PI were measured preoperatively and at 2 years. Change in PT was compared between patients with matched or mismatched LL based on a common clinical definition (LL = PI + 10) and a research-driven model (LL = 0.56 PI + 33.43). ResultsThirty-eight percent of patients had decreased LL from before surgery to 2 years after surgery. These patients had significantly higher rates of increased PT (73%) than patients without decreased LL (40%). Multivariate regression demonstrated that change in LL, LL within fusion, and GSA had a significant predictive effect on PT (p < .001). Using either definition of LL, patients with LL less than 2 standard deviations from predicted values were more likely to have increased PT. ConclusionsIatrogenic loss of LL commonly occurs in spine fusion for AIS and is associated with a reciprocal increase in PT. As such, spinal fusion in AIS can have unintended effects on sagittal alignment with currently uninvestigated potential consequences in the future.

Bone Grafting Options in Children

Retrospective review of the literature. To review the current literature as well as recent trends in bone grafting techniques available for children. The currently accepted gold standard in bone grafting for adolescent idiopathic scoliosis (AIS) is autogenous iliac crest. Due to questions concerning complications such as donor site pain, other options have been explored, including various allograft sources, demineralized bone matrix, and bone morphogenetic protein. A review of the current medical literature was completed and additional case examples are presented. A review of the literature reveals that up to 31% of patients have persistent pain at 2 years post surgery when autogenous iliac crest bone graft is harvested. Allograft supplementation of local autograft has been demonstrated in the literature to be as effective as autogenous iliac crest bone grafting in contributing to a successful posterior spinal fusion in patients with AIS. Modern demineralized bone matrix formulations have been found in both animal models as well as in a recent retrospective clinical review to contribute to a successful posterior spinal fusion in AIS. Bone morphogenetic protein has been shown to contribute to a successful posterior spinal fusion in complex pediatric spinal deformity patients. At 2 years follow-up, patients who underwent a posterior instrumented spinal fusion that was not augmented with any bone graft appear to have successful spinal fusions. Although autogenous iliac bone graft remains the benchmark to which bone grafting materials are compared, other options including the placement of no bone graft at all provides similar fusion rates in patients with AIS.

What Impact Does Spinal Deformity Correction for Adolescent Idiopathic Scoliosis Make on Quality of Life?

: Literature review. : To identify scientifically sound studies that have reported changes in quality of life (QOL) after spinal deformity correction in patients with adolescent idiopathic scoliosis (AIS) and to discuss these findings. : Few studies have been published. Most are retrospective cohort studies and lack both preoperative and postoperative data for the outcome in terms of QOL. : A review of existing literature with the emphasis on spinal fusion for AIS and outcome as measured by health-related QOL was performed. : Thirteen studies of various quality were found after reviewing the papers. Only 3 of them contained both preoperative and postoperative data on QOL, using the SRS-22/-24. They all reported a statistically significant improvement in some of the domain scores. The clinical implications of these findings are unclear, as the minimal clinically important differences for SRS-22/-24 have not yet been established. : Weak evidence (Level IV) exists in the literature that spinal deformity correction for AIS does not significantly impact QOL in short-term or mid-term. The interpretation of this must be that there were no serious adverse events after surgery.